Synthesis And Application Of Heteracalix[2]arene[2]triazine Derivatives

Easy accessibility,tunable conformational structures and versatile molecular recognition properties of heteroatom-bridged calixarenes or heteracalixaromatics have been seen.Thus,this class of molecules had been widely used in moleculars recognition,ions recognition,fluorescent chemical sensors and other fields.In recent years,a good selective recognition for transition metal ions,anions and neutral molecules of heteracalixarenes modified by containing heteroatom（such as O,N,and S）groups had been found and widely concerned.In this paper,tetraoxacalix[2]arene[2]triazine was synthesized effectively through a one-pot reaction of cyanuric chloride and resorcinol as raw materials.Then three series of new tetraoxacalix[2]arene[2]triazine derivatives were designed and synthesized by nucleophilic substitution reactions.New compounds were identified by ¹H NMR,¹³C NMR,HRMS/LRMS and IR spectra.Furthermore,the binding properties of the newly synthesized calixarenes to ten metal ions(Cu²⁺,Ni²⁺,Fe³⁺,Fe²⁺,Pb²⁺,Mn²⁺,Ag⁺,Zn²⁺,Co²⁺,Al³⁺)and eighit anions（NO₃^-,Cl^-,Br^-,ClO₄^-,I^-,H₂PO₄^-,CH₃COO^-,HSO₄^-）was investigated by UV-vis and fluorescence titration,respectively.The experimental results show that good specific selective recognition for Fe³⁺of compounds 7a,7b,7c and 23 was seen,which was not disturbed by other metal ions.And it was confirmed by ¹H NMR that Fe³⁺was probably located in the cavity formed by two triazines of the compounds 7a or 7c,when Fe³⁺was recognized by them.Ions of Cu²⁺and Fe³⁺could simultaneously be recognized by compounds14 or 15.The stoichiometric ratios and association constants of the compounds to recognized ions were calculated by using the non-linear fitting equation deduced by Ma Zhengyue.The detection limit of the compounds to recognized ions and the Gibbs free energy of ions recognition reaction were calculated.In summary,ion-selective recognition properties of new tetraoxacalix[2]arene[2]triazine derivatives for Fe³⁺were good,and ions detection limits were low,which provided the basis for the development of new ions recognition reagents.